import str_util
from str_util import *

print("======================================")
print(str_reverse("今天炸鸡买一送一"))
print("======================================")
print(str_util.substr("The world is a good place.", 3, 16))

from file_util import *

print("======================================")
print(append_to_file("Yardon_check.txt", "黄鹤一去不复返，白云千载空悠悠。"))
print("======================================")
print(print_file_info("Yardon_check.txt"))
